Mechanical seal for selenium rectifier cells



Nov. 9,1948. r s. BLUMENTHAL ',2,453,6l8

MECHANICAL SEAL FOR SELENIW RECTIFIER CELLS Filed D66. 29, 1945 P I W1 N N i: f m

INVENTOR d2! Hume-1111141 BY 1 ATTORN EY UNITED s'rA'rss PATENT'OFFICE.

MECHANICAL SEAL FOR SELENIUM RECTIFIER CELLS I Sol .Blamenthai, Indianapolis, Ind., assignor to P. R. Mallory a 00., Inc Indianapolis, Ind., a corporation of Delaware Application December 29 1945, Serial No. 688,049

l 1 This invention relates to rectiiiers and to an improved sealing arrangement therefor.

An object of the invention is to provide an improved sealing arrangement for rectifiers.

Other objects of the invention will be apparent 5 produced by the rect fie s not a ob y aifrom the following description and accompanyfected by such construction. Furthermore, the ing drawings taken in connection with the apparts required are simple and inexpensive and pended claims. these parts may be quickly and easily assembled.

The invention comprises the features of con- Referring now to the drawings i detail. the struction, combination of elements, arrangement rectifier may mpri ii pl y f cells of parts and methods of manufacture and opermounted on a, suitable supporting shaft ll. Each ation referred to above or which will be brought rectifier cell, i example Shown. comprises a out and exemplified in the disclosure hereinafter metal disc l2 carrying a layer of selenium as at set forth, including the illustrations in the drawis upon which may bedisposcd a suitable counter ss. electrode it formed, for example, by spraying In the drawings: a layer of powdered metal or other suitable con- Figure 1 is a front elevational view of the recducting compound upon the selenium. It will be tifier with parts broken away to show the detailed understood by those skilled in the art that an features of onstructi n; and Y extremely thin blocking layer. not shown, is t Figure 2 is a sectional .view taken along the formed by interaction between the selenium and line 2-2 of Figure 1. the counter electrode, the rectifying action being According to one aspect of this invention. an due to the effect of this blocking layer. Howimproved mechanical sealing arrangement is ever, my invention does not depend on the parprovided whereby the active surface of the recticular rectifying compound used nor the manner tiller is enclosed within a sealed chamber in in which the rectification takes place as it will order to permit efficient operation of the rectibe apparent that the inventlon is applicable to fier when subjected to normal or extreme atother types of rectifier, such, for example, as mospheric attacks as by salt moisture, or fungus. copper-oxide rectifiers. The thickness of the While a preferred embodiment ofthe invenselenium layer and the counter electrode, which tion is described herein, it is contemplated that is preferably only a few thousandths of an inch, considerable variation may be made in the is greatly exaggerated on th drawing for purm h 01' Procedure and the construction of poses of illustration. Preferably, the active recparts without departing from the spirit of the tifying layer is does not cover the entire surface invention. In the following description and in of the disc but, instead, is applied so as to leave h claims. p rt w h i n ifie y fi a peripheral inactive portion I4 and a central names for convenience. but they are intended to inactive portion l5. be as generic in their application to similar parts A metal cap it is providedto seal the periphas the art will permit. eral portions of the disc I2- The cap i8 may According to a preferred manner of construchave a peripheral flanged portion H which entiOn. a rectifier electrode or disc having n active 40 gages the inactive side or the disc I2 to provide surface for current rectification is mounted on a sealed joint. As shown, a plastic washerv is asuitabie shaft or other ppo t- A n is promay be interposed between the ca it and the v ded for en agin the peripheral surfates 0f the inactive surface ll of rectifier disc to facilitate electrode in order to provide an eifective seal the sealing action and the assembly'of the cap against atmospheric attacks. A contact member upon t rectifier also. The ca may also be for the active surface is mounted between the provided with central aperture is which is of el t e n the sealing 1 this ontact being appreciably greater diameter than the shaft ll. provided with an external flanged portion which A Contact member 2|, hi may honvenis adapted o ontact w t an cen ct iently be a resilient spring washer, is mounted iler cell. A sealed joint is formed between the on th shaft b t e the cap is and th re rectifler electrode, the cap, and the contact meme tlfl r dis [2. The spring member 2| isurged ber adjacent t pportin shaft 50 that the into engagement with the active surface is of active surface is enclosed within a sealed chamthe rectifier disc and affords a large area of con-' her. When a pl ra ty f ce s e placed t tact therewith. The contact member 2| further gether in an assembly, cont is made between t5 comprises a contact portion 22 which is seated the adjac t cells by t external o t upon the shaft II and extends through the apertiOhB. and the s alin m ns 0!! th Shaft D ture is in the sealing cap. The outer end of the vides th p p p ing between adjacent contact portion 22 may be upturned as at 22 so rectifier cells. Such an arrangement provides a as to contact the surface of the adjacent rectifier 00 disc 12. It will beunderstood that the contact strong mechanical assembly which greatly miniClaims. (Cl. -368) imizes damage caused by shocks or strains and all parts which are adlacent to the current carrying portions of the rectifier may be good conductors of heat so that dissipation of the heat portion 22 is either insulated from the shaft II Washers and 28 are mounted on the contact portion 22 and are effective to seal the joint between said contact portion 22 and the cap l6. Since the aperture i9 is of greater diameter than the shaft II, the cap it does not touch the contact portion 22 so that the washers also serve to insulate these parts.

When a plurality of rectifier cells are assembled to form a complete unit, the upturned end portion 23 of each cell is compressed between the washer 2B and the adjacent disc I! to thereby afford a good electrical contact and provide additional sealing action. Moreover, the washers 24, 25, and 20, as a group, serve to maintain the proper spacing between adjacentrectifler units. It is an important feature of the invention that the active rectifying layer ll is enclosed .within a sealed chamber C defined by the cap it, the sealing washer i3, and the disc I! so that the reactive compounds which are used for rectification are protected from atmospheric attacks as active surface, said member having a contact portion extending through the aperture in said cap, and a plurality of washers for providing a seal between an inner portion of said rectifier plate, the portion of said cap adjacent said aperture and the contact member adjacent said shaft. said washers being effective to insulate said cap from said contact member.

3. A dry surface rectifier comprising a central supporting shaft and a plurality of rectifier cells mounted on said shaft, each cell comprising an apertured rectifier plate mounted on said shaft and having an active surface for current rectification-which is bounded by central and.

peripheral inactive surfaces, an apertured metal cap including a main body portion and an outer flange, said "flange being used for sealing the peripheral inactive portions of said rectifier plate,

a contact member for said active surface mounted on the shaft between the'rectifier plate and themain body portion of said cap, said contact memher having a contact portion extending through cap adjacent said aperture, and said contact member adjacent said shaft whereby the active surface of the rectifier plate isenclosed within a sealed chamber, said sealing means providing the proper spacing between adjacent cells of the rectifier.

by salt moisture or fungus. It will be further apparent that the invention is not limited in its application but may be used with rectifiers of various types having various sizes and shapes and utilizing copper oxide or any other suitable compound instead of selenium.

Although the present invention, as to its obiects and advantages, has been described herein as carried out in a specificembodiment thereof, it is not desired to be limited thereby but it is intended to cover the invention broadly within the spirit and scope of the appended claims.

What is claimed as new and desired to be secured by Letters Patent isz 1. A sealed dry disc rectifier cell comprising a supporting shaft, an apertured metal rectifier disc mounted on said shaft and having'anactive surface for current rectification, means including an annular apertured cap with a main body portion and an outer flange, said flange being used for sealing the peripheral portions of said rectis fier disc, a resilient contact washer for engaging said active surface mounted on the shaft between the rectifier disc and said body portion of said cap, said contact washer having a portion extending through the aperture'in said cap for .contact with an adjacent rectifier disc, and

means associated'with said shaft for providing a seal between an inner portion of said rectifier disc, the portion of said cap adjacent said aperture, and the contact washer adjacent said aperture whereby the active surface of the rectifier cell is enclosed within a sealed chamber.

5 Number tions" of said rectifier plate, a resilient electrical contact washer for said active surface mounted between the rectifier plate and said body portion of said cap, said contact washer having an electrical contact portion extending through and insulated from said cap for contact with an apertured rectifier plate of an adjacent rectifier cell, and means for providing a seal between an inner portion of said rectifier plate, the portion of saidcap adjacent said aperture thereof, and the electrical contact washer adjacent said shaft whereby the; active surface of therectifier plate and the portion-of said washer in contact therewith is enclosed within a sealed chamber, said sealing means providing the proper spacing between adjacent cells of the rectifier.

- SOL BLUMENTHAL.

aeralmucas crran The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Levy May 29, 1928 Addink et al Nov. 17, 1942 Kotterman Mar. 7, 1944 Kay Aug. 28, 1945 FOREIGN PATENTS Country Date Switzerland Nov. 1, 1933 Germany July 6, 1940 Number 

